Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 12, Problem 32P
Give at least one example of a chromosomal structure or function affected by the following mechanisms for modulating chromatin structure:
| a. | Posttranslational changes of the normal histone found in the nucleosome |
| b. | Nucleosomes with variant histones encoded by special genes. |
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A cell is homozygous for a LOF mutation in the histone acetyltransferase (HAT) gene. Which of the following is/are true?
a. Chromatin in the cell will be more condensed than usual, decreasing expression of genes that should be expressed.
b. This will lead to histones with more positive charges on their tails, increasing the interaction between histones and the DNA backbone.
c. This will lead to a decrease in DNA methylation and therefore cause an increase in gene expression.
d. Chromatin in the cell will be less condensed than usual, increasing expression of genes that should not be expressed.
Write the word TRUE if the statement is correct and if false, replace the
underlined words with the correct one.
1. Heterochromatin is typically gene-rich and composed of
loosely-packed DNA that is transcriptionally active.
2. Molecular switches regulate the expression of genes by directing
where and when genes should be turned on or off depending on the
cell signal.
3. DNA Methylation and acetylation of histones are inverselycorrelated
4. Specialized cells produce specialized proteins derived from luxury
genes which are constitutively expressed.
5. In mammals, methylation patterns that regulate DNA structure and
gene expression become evident from the gastrula stage.
Explain the following terms: Non-histone Chromosomal (NHC) proteins, euchromatin & Heterochromatin.
Chapter 12 Solutions
Genetics: From Genes to Genomes
Ch. 12 - For each of the terms in the left column, choose...Ch. 12 - Many proteins other than histones are found...Ch. 12 - What difference exists between the compaction of...Ch. 12 - What is the role of the core histones in...Ch. 12 - a. About how many molecules of histone H2A would...Ch. 12 - The enzyme micrococcal nuclease can cleave...Ch. 12 - a. What letters are used to represent the short...Ch. 12 - About 2000 G bands are visible in a...Ch. 12 - Suppose you performed a fluorescence in situ...Ch. 12 - Which of the following would be suggested by a...
Ch. 12 - For each of the following pairs of chromatin...Ch. 12 - a. Drosophila b. Humans Give examples of...Ch. 12 - One histone modification that is seen consistently...Ch. 12 - Recently, scientists constructed a transgene that...Ch. 12 - Drosophila geneticists have isolated many...Ch. 12 - On the following figures, genes A and B are on the...Ch. 12 - Prob. 17PCh. 12 - The first page of this chapter displays photos of...Ch. 12 - The human genome contains about 3 billion base...Ch. 12 - The mitotic cell divisions in the early embryo of...Ch. 12 - In an experiment published in the journal Cell in...Ch. 12 - a. What DNA sequences are found at the telomeres...Ch. 12 - Prob. 23PCh. 12 - a. In a fluorescent in situ hybridization FISH...Ch. 12 - If you are comparing the two telomeres in each...Ch. 12 - a. What DNA sequences are commonly found at human...Ch. 12 - On the graphs presented in Problem 21, no data is...Ch. 12 - Prob. 29PCh. 12 - Prob. 30PCh. 12 - In the 1920s, Barbara McClintock, later a Nobel...Ch. 12 - Give at least one example of a chromosomal...Ch. 12 - Cornelia de Lange syndrome CdLS is a rare human...Ch. 12 - a. Give at least three examples of types of...Ch. 12 - A number of yeast-derived elements were added to...Ch. 12 - Prob. 36PCh. 12 - The completely synthetic yeast chromosome Syn III...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Like Hurler syndrome, Fabry disease involves an abnormal accumulationof substances within lysosomes. However, the lysosomes of individuals with Fabry disease show an abnormal accumulation of lipids. The defective enzyme is α-galactosidase A, which is a lysosomal enzyme that functions in lipid metabolism. The defect causes cell damage, especially to the kidneys, heart, and eyes. The gene that encodes α-galactosidase A is found on the X chromosome. Let’s suppose a phenotypically unaffected couple producestwo sons with Fabry disease and one phenotypically unaffecteddaughter. What is the probability that the daughter will have anaffected son?arrow_forwardAn old genetic observation is that a normally active gene will be silenced if it is moved by transposition or crossing over from an uncondensed (euchromatic) region to a heavily condensed (heterochromatic) region of a chromosome. Assume the euchromatic chromatin containing the active gene is surrounded by heterochromatic chromatin immediately after insertion. Please explain in terms of the control of histone modification why the normally active gene is silenced when it becomes surrounded by condensed regions. (Do not explain how histone modification causes chromatin condensation.)arrow_forwardWhen an injury occurs to the skin, the epithelial cells near the wound are signaled to react (by proliferating, migrating, and/or differentiating) to restore the skin in the wound. To investigate the healing process, researchers removed a small area of epithelial cells from the skin of mice, causing a wound. The researchers monitored the acetylation status of histone H4 at lysines K5, K8, and K16 on days 1, 4 and 9 after the wound was made. Cells in three regions were studied (see Figure A below): Normal epithelial cells not directly near the wound Epithelial cells adjacent to the wound The cells repopulating/repairing the wound (referred to as an “epithelial tongue” early in the process and “closed wound” later in the process) The percent of cells that were positive for H4 acetylation was recorded. The bar graph in Figure B below shows data for Days 4 and 9 for cells examined in the wound. While this experiment focused on mice, we may be able to apply the results to…arrow_forward
- Discuss the levels of chromosomal organization with reference to the following terms: a. nucleotide b. DNA double helix c. histones d. nucleosomes e. chromatinarrow_forwardBase on your knowledge of DNA, chromosomes and epigenetics and upon examining the picture below, name two epigenetic factors and at least one non-epigenetic factor present on this picture. [HINT: which of the factors shown on the picture do you expect to change based on the interactions with an environment and which you expect unchanged?] Methyl Group DNA Chromatin Epigenetic Factor Histone Histone Tails Chromosomearrow_forwardThe interphase is the part of the eukaryotic cell cycle that is most transcriptionally active. Gene regulation during this phase involves changes in the chromatin. a) What is chromatin? b) How can the chromatin structure change?arrow_forward
- Describe how reversible chemical changes to histones are linked to chromatin modification.arrow_forward7. Progression from metaphase to anaphase in the cell cycle, and subsequent exit from anaphase, requires sequential events involving the Anaphase Promoting Complex (APC). APC is a multi- protein complex that has ubiquitin ligase activity (see pp. 611-612 in your textbook re: ubiquitin). When APC adds adds ubiquitin to a substrate protein, the protein is targeted for degradation by the proteasome. Two important substrates of APC are the proteins securin and cyclin B. Destruction of securin allows the separation of sister chromatids at the beginning of anaphase, whereas subsequent destruction of cyclin B allows cells to exit anaphase (see Figure 24-18 in your textbook). APC Cdh-1 Cdc20- Securin Mitotic cyclins Cohesin G1 Metaphase Anaphase For APC to bind specific substrates, it requires unique adaptor proteins that help it to recognize its substrates. The adaptor protein Cdc20 allows APC to recognize and ubiquitinate securin, while the adaptor Cdh-1 allows APC to recognize and…arrow_forwardThe retinoblastoma tumor suppressor gene Rb (RB1) codes forthe retinoblastoma protein (pRB). pRB prevents the progression of the cell cycle through G1 if DNA has been damaged. Itdoes so in part because it binds a transcription-activatingdimer referred to as E2F-DP. The pRB-E2F/DP complex recruits a histone deacetylase to chromatin. Explain.arrow_forward
- A cultured mouse cell line has a mutation in a gene encoding a ribosomal protein. The mutant protein impairs the fidelity of translation such that incorrect amino acids are incorporated at higher rates than normal during protein synthesis. It also slows the rate of mRNA translation and increases the duration of the cell cycle, i.e., the mutant cells grow and divide more slowly. Researchers noted that these cells express higher levels of chaperone proteins than normal cells. Which of the following is the most likely explanation for the elevated chaperone levels.arrow_forwardExplain, How does histone acetylation alter chromatin structure?arrow_forwardA cell inherits a mutation in a gene that results in a transcription factor, called NF-kB, constantly being in its active conformation. When active, NF-kB stimulates the expression of cyclins that promote progression of the cell cycle, regardless of other conditions. As a result of this mutation, how would this cell's phenotype be affected by this mutation? A) This cell would have a cancer phenotype B) This cell would grow larger in size, but would never divide C) This cell would likely undergo apoptosis D) This cell would not duplicate its chromosomes .arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning
Human Heredity: Principles and Issues (MindTap Co...
Biology
ISBN:9781305251052
Author:Michael Cummings
Publisher:Cengage Learning
QCE Biology: Introduction to Gene Expression; Author: Atomi;https://www.youtube.com/watch?v=a7hydUtCIJk;License: Standard YouTube License, CC-BY